Pocket Casts is open source. (I know you didn't say otherwise, but there's potential for misunderstanding given the wording.)

Could you describe what it was that made you switch?

Not the OP but for me I switched before they went opensource and I was having issues with how Patreon feeds were imported into Pocketcasts. Can't really remember the specifics but if I remember correctly their server was doing some episode caching and it was going all funky.

I stay with Antennapod now because it's very actively maintained and because of the Nextcloud gpodder¹ app and the Nextcloud Repod app². Lets me have a web player and sync entirely within my own infrastructure.

[1] https://apps.nextcloud.com/apps/gpoddersync

[2] https://apps.nextcloud.com/apps/repod